Syntax to move backwards in LinkedList?

doubly-linked-list, java

Solution

`LinkedList` has a `listIterator(int)` method. So you can use:

// Start at the end...
ListIterator<Foo> iterator = list.listIterator(list.size());
while (iterator.hasPrevious()) {
    Foo foo = iterator.previous();
}

That doesn't prove that it's a doubly-linked list - that could be implemented very inefficiently in a single-linked list, for example - but that's how I'd go about iterating over a linked list backwards.

Problem

i know that LinkedLists are implemented in a doubly linked way, so each node has a next and a previous pointer. however, i couldn't find what syntax to use to access the previous nodes? i looked on the java api, and there is a method to iterate through a linkedlist backwards. that to me, implies that there is an easy way to access previous nodes P:. i am trying to design an experiment to prove that LinkedLists isn't just a singlely linked list but i can't think of how to do so without moving backwards in linkedlists. please explain to me how to move backwards if it is possible, thank you very much.

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